The massive U.S. bomb dropped on an Islamic State cave complex in Afghanistan last week killed militant fighters from Pakistan, Tajikistan, Uzbekistan, Russia, India, and other countries, an Afghan official said.

"Most militants killed in the attack were from Pakistan, India, Philippines, and Bangladesh," Mohammad Radmanish, a spokesman for the Afghan defense ministry, said on April 18.

The GBU-43 bomb, nicknamed MOAB for "massive ordnance air blast" or "mother of all bombs," killed 96 Islamic State militants, including four key IS leaders on April 13, the Pentagon and Afghan officials have said.

They said it also destroyed a 300-meter long cave system, along with large amounts of light and heavy weapons and munition.